The Program Project entitled "Neurobiology of Mild Cognitive Impairment in the Elderly" brings together a number of basic scientists and clinician scientists from Chicago and outside universities. The project will be based at Rush Presbyterian-St. Luke's Medical Center in Chicago. The Program Project consists of an Administrative Core with a Clinical/Tissue Distribution component and a Statistics and Data Management Core. In addition the following four research projects complete the program: 1) Tau abnormalities and Mild Cognitive Impairment in the Elderly (John Trojanowski, University of Pennsylvania, project leader); 2) Age-Related Neuropathology and Mild Cognitive Impairment in the Elderly (Dennis Dickson, Albert Einstein College of Medicine, project leader); 3) Cholinergic Basal Forebrain Neurotrophic Abnormalities and Mild Cognitive Impairment in the Elderly (Elliott Mufson, Project Leader); and Synaptic Abnormalities and Mild Cognitive Impairment in the Elderly (Steven DeKosky, University of Pittsburgh, project 1Leader). Each core will support all of these research projects. Moreover, these projects will receive clincial data and tissue samples from the NIA funded Rush ADC Religious Orders Study Core and the Neuropathology Core for all projects.